An investigation was carried out into the prevalence of thermophilic Campylobacter subspecies (spp.) and Cryptosporidium spp. in fresh fecal specimens collected from members of the gull family (Larus spp.) from three coastal locations of Northern Ireland. A total of 205 fresh fecal specimens were collected from gulls, of which 28 of 205 (13.7%) were positive for Campylobacter spp. and none of 205 for Cryptosporidium spp. Of these campylobacters, 21 of 28 (75%) isolates obtained belonged to the urease-positive thermophilic Campylobacter (UPTC) taxon, followed by five of 28 (17.9%) Campylobacter lari and 2/28 (7.1%) Campylobacter jejuni. It is significant that seagulls are the sole warm-blooded animal host of this bacterial taxon in Northern Ireland. It is proposed that physiological adaptation to starvation by gulls may lead to increased concentrations of urea through energy production from protein, yielding increased levels of urea for metabolism by UPTC organisms. In general, the possibility exists that environmental contamination of surface waters with campylobacters might be mediated by wild birds (such as gulls), where such waters are used for recreational purposes or where such waters are consumed untreated, might represent a risk to public health.